[Users] SPM host in unknown status

Description of problem: i have 2 nodes ovirt-node1.local Non Responsive SPM ovirt-node2.local Up None The SPM node stuck in Non-responsive status, it can't be actived, all vms in the node went into Unknown status and the master vm domain became inactived when i do "Maintenace" action to node1, it says: Error: Cannot switch Host to Maintenance mode. Host still has running VMs on it and is in Non-Responsive state. but there has no vm running in node1 , it only has 2 vms in Unknown status Because I can't active the SPM host , so i can't active the vm storage domain 1,How can i migrated the SPM role to other host in my data center , such us node2? 2,How can i send the node1 to UP status?(I have did 'confirm the host has been Rebooted' action , and rebooted the node1, but it did no sense)